Torch head



Sept. 30, 1958 w. J. cA'lRNs TORCH HEAD Filed Nov. 24, 1954 UnitedStates Patent O TORCH HEAD Walter J. Cairns, Melrose, Mass.,

Torch Corporation, Boston, Massachusetts assignor to Browning Mass., acorporation of This invention relates to improved construction of thehead of a torch intended for use with liquid fuel and oxygen. Foreffective operation with liquid fuel, the fuel must be completelyvaporized by the time it issues from the oriiices at the extremity ofthe tip to support the flame. For this purpose the tip is designed toIbe strongly heated by the llame. It is practically necessary toinsulate the tip from the remainder of the head since these parts are ofmetal and a free conduction of heat from the tip would soon make theentire head too hot. Heat -barriers have been used between the tip andthe body portion of the head, but these have given trouble due to theirtendency to deform under the heat and pressure to which they aresubjected in use. According to the present invention a washer of heatinsulating and heat resistant material is interposed between the tip andthe body portion of the torch head, and the parts are so formed thatwhen assembled they completely enclose and conne the heat insulatingwasher, thus preventing any deformation of the washer.

An embodiment of the invention is illustrated in the drawing, of which-Figure 1 is a perspective view of a heat-insulating washer;

Figure 2 is an elevation of the inner member of a torch tip, with aheat-insulating washer thereon;

Figure 3 is an elevation of a torch head, showing in section -a portionof the body, the tip, and means for securing the tip to the body.

A torch head is shown in Figure 3 with pipes 12 and 14 connected theretofor supplying liquid fuel and low-pressure oxygen, respectively, and apipe 16 for highpressure oxygen. A stem 20 controls a needle valvewithin the head for atomizing the fuel as it is mixed with low-pressureoxygen in the usual manner. The mixture flows down through a passage 22into mixing chambers 24 in the torch tip 26 where the Vaporization ofthe atomized fuel is completed before the stream is discharged throughline ducts 28 and a discharge orifice 30 at the extremity of the tip. Anaxial passage 32 communicates with the pipe 16 to deliver high pressureoxygen through a similar passage 34 in the tip 26 to the dischargeorifice 30.

The torch tip 26 may consist of an inner member 40 and an outer tubularmember 42 which encloses the lower portion of the inner member. Theouter member 42 has a radial flange 44 at its upper end to provide ashoulder engageable by a collar 50 to draw the tip tightly against thebody portion of the head 10. The body portion of the head is cylindricalso that it has a circular face at its lower end. The tip has a similarcircular face at its upper 2,854,067 Patented Sept. 30, 1958 ICC end.Between these faces is interposed an insulating disk 52 ofheat-resistant as well as heat-insulating material such as a polymer oftetrailoro-ethylene, described in U. S. Patent No. 2,230,654, pressedasbestos or an equivalent. The disk has two holes 54 and 56 to registerrespectively with the passagse 22 and 32, and its diameter is equal tothose of the mutually confronting end faces of the body and tip of thetorch head.

In order to maintain the tip accurately in line with the body portion ofthe head, the upper end of the tip has a nipple 58 projecting upwardaxially and fitting into a corresponding recess in the body of the head,this recess being a slight enlargement of the lower end of the passage32. The nipple 58 surrounds the upper end of thepassage 34. Anotherpositioning element for the tip is a thimble 60 the upper end of whichlits in a slight enlargement of the passage 22, the lower end tting intoa recess in the tip communicating with 4the mixing chambers 24. Thecentral hole 56 is snugly tted by a portion of the nipple 58. The hole54 is snugly fitted by a portion of the thimble 60. Hence when the headis assembled as shown in Figure 3, the broad faces of the disk 52 areengaged and confined by the end faces of the body and tip, the outeredge surface of the disk is engaged and confined by the collar 50, andthe inner edge surfaces, that is, the walls of the holes 56 and 54, areengaged and conned by the nipple 58 and thimble 60 respectively. Theentire surface area of the disk is thus coniined so that spreading orother deformation of the disk is positively prevented. This results in amuch longer life of the disk and a more satisfactory performance by thetorch as a whole.

I claim:

A torch head comprising an elongated body member terminating in a planarend face, a tip member terminating in a planar end face, a disk ofcompressible heat-insulating material disposed between and directlyengaged by said end faces, securing means for moving said end facestoward each other to a disk-compressing position and for maintaining thesame in said position, said members having spaced alignedfluid-directing passages formed therein, said disk having holestherethrough registering with respective aligned passages in saidmembers, said securing means having an inner surface portion rigidlyengaging the entire peripheral surface of said disk, and means extendingthrough said disk holes and rigidly engaging the entire surface of thewalls of said disk holes, said means comprising a nipple integral withsaid tip member and projecting into oneof said passages in the bodymember and a thimble extending at one end into the other passa-ge in thebody mem-ber and at the other end into the corresponding passage in thetip member.

References Cited in the le of this patent UNITED STATES PATENTS1,242,243 Rose Oct.- 9, 1917 1,689,551 Hammond Oct. 301928 1,926,438Fausek et al. Sept. 12, 1933 2,204,756 Hasse June 18, 1940 FOREIGNPATENTS v 499,959 France Dec. 3, 71919 515,537 Germany Jan. 7, 19311,056 Great Britain 1907 140,529 Switzerland Aug. 16, 1930

